Never ever use thread tape on a bleed nipple.If I only crack the nipple, then hardly any fluid comes out, if I crack it more, then fluid seeps out from around the threads. Someone suggested putting a few wraps of yellow teflon tape on the top threads of the bleed nipples. Anyone tried this or have any thoughts/advice?
Do you have bleed nipples with internal check valves? At the first crack these will need some pressure to push the spring back and open the bleeder.
If it is a standard type bleed nipple and only flows passed the thread there is something wrong in the nipple or the seat. Remove and inspect the seat and the base of the nipple and check that it is not blocked. The seal is at the taper and seat not on the thread.
If you are relying on a sealer on the thread to seal a bleed nipple you have a failure iminent. A lubricant on the thread to stop corrosion or pick up is good maintenance.